Nano-engineering in zinc-based catalysts for CO2 electroreduction: Advances and challenges

Electrocatalytic CO₂ reduction (CO₂RR), an emerging sustainable energy technology to convert atmospheric CO₂ into value-added chemicals, has received extensive attention. However, the high thermodynamic stability of CO₂ and the competitive hydrogen evolution reaction lead to poor catalytic performances, hardly meeting industrial application demands. Due to abundant reserves and favorable CO selectivity, zinc (Zn)-based catalysts have been considered one of the most prospective catalysts for CO₂-to-CO conversion. A series of advanced zinc-based electrocatalysts, including Zn nanosheets, Zn single atoms, defective ZnO, and metallic Zn alloys, have been widely reported for CO₂RR. Despite significant progress, a comprehensive and fundamental summary is still lacking. Herein, this review provides a thorough discussion of effective modulation strategies such as morphology design, doping, defect, heterointerface, alloying, facet, and single-atom, emphasizing how these methods can influence the electronic structure and adsorption properties of intermediates, as well as the catalytic activity of Zn-based materials. Moreover, the challenges and opportunities of Zn-based catalysts for CO₂RR are also discussed. This review is expected to promote the broader application of efficient Zn-based catalysts in electrocatalytic CO₂RR, thus contributing to a future of sustainable energy.